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Objective excyclotorsion increases with aging in adults
1Department of ophthalmology, Wakaba Eye Hospital, Tokyo.
Strabismus
|September 27, 2022
Summary
The disc-fovea angle (DFA), a measure of eye cyclotorsion, increases with age. This study found that DFA is larger in females, the left eye, and the non-dominant eye.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- The disc-fovea angle (DFA) objectively measures cyclotorsion.
- Previous reports suggest DFA increases with age.
Purpose of the Study:
- To investigate the effects of age, sex, and eye laterality on DFA.
- To quantify age-related changes in cyclotorsion.
Main Methods:
- Retrospective analysis of fundus photographs from 249 participants (aged 44-81 years).
- Exclusion criteria included poor visual acuity, high axial length, strabismus, and fusion-affecting ocular diseases.
- DFA measured using digital fundus photography; total DFA calculated as the sum of right and left eye DFAs.
Main Results:
- Older adults (Group III, ~81 years) showed significantly larger left-eye and total DFA compared to younger adults (Group I, ~44 years).
- Female participants exhibited significantly larger total DFA than males.
- The left eye had a significantly larger DFA than the right eye.
- DFA was significantly larger in the non-dominant eye compared to the dominant eye.
Conclusions:
- DFA shows a slight but significant increase with age.
- Female sex and left-eye dominance are associated with larger DFA.
- Cyclotorsion, as measured by DFA, is influenced by age, sex, and eye dominance.
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